I want to use the Redirect to Action result on this code which gives a null but i have several if statements and the code is becoming more complex to build need a solution on how i could use the Redirect to Action which outputs null, help please?
public ActionResult Convert(double temperature, string convertTo)
{
ViewBag.Temperature = temperature;
ViewBag.ConvertTo = convertTo;
if (convertTo.Equals("Celsius"))
{ ViewBag.ConvertedTemperature = this.FahrenheitToCelsius(temperature); }
else
{ ViewBag.ConvertedTemperature = this.CelsiusToFahrenheit(temperature); }
return View("Convert");
}
The error message would really help. But it seems like you'd need to make your temperature parameter nullable, like so:
public ActionResult Convert(double? temperature, string convertTo)
Then you could check for null and return RedirectToAction:
if (temperature == null)
return RedirectToAction("ActionName", "ControllerName");
You'll also need to do the following to get the temperature value in your conversion methods:
temperature.Value
Hope this helps.
Related
I am facing a problem in searching a exact record by LINQ query method in ASP.NET Web API my controller. This is my code:
[HttpGet]
[Route("api/tblProducts/AllProductbySearch/{SearchText}")]
[ResponseType(typeof(IEnumerable<tblProduct>))]
public IHttpActionResult AllProductbySearch(string SearchText)
{
IEnumerable<tblProduct> tblProduct = db.tblProducts.Where(x=>x.PrdKeyword.Contains(SearchText)).AsEnumerable();
if (tblProduct == null)
{
return NotFound();
}
return Ok(tblProduct);
}
In this I am searching the record with value have keyword column and getting the result but problem is that it is not giving exact result for example if in database two record have keyword column value like shirt and another have Tshirt
Then if I pass shirt in SearchText or pass tshirt in SearchText it is giving both record while I want one record which exact match with SearchText. Please help me
My updated action method code is:
[HttpGet]
[Route("api/tblProducts/AllProductbySearch/{SearchText}")]
[ResponseType(typeof(IEnumerable<tblProduct>))]
public IHttpActionResult AllProductbySearch(string SearchText)
{
IEnumerable<tblProduct> tblProduct = db.tblProducts.Where(x => CheckWord(x.PrdKeyword, SearchText)).AsEnumerable();
if (tblProduct == null)
{
return NotFound();
}
return Ok(tblProduct);
}
private bool CheckWord(string source, string searchWord)
{
var punctuation = source.Where(Char.IsPunctuation).Distinct().ToArray();
var words = source.Split().Select(x => x.Trim(punctuation));
return words.Contains(searchWord, StringComparer.OrdinalIgnoreCase);
}
But is throwing the same error - http 500
EDITED 2
Added ToList() - db.tblProducts.ToList().... In this case we retrieve all data from Data Base and filter them in memory. If we don't retrieve all data before filtering .Net tries to create request to SQL with filtration and can't because there are .Net methods as CheckWord().
I think we can get required data without retrieving all table into memory, but don't know how. As variant we should write specific Stored Procedure and use it. Get all into memory is a simplest way (but not faster)
Please, look at this post Get only Whole Words from a .Contains() statement
Actually, for your case solution can be:
IEnumerable<tblProduct> tblProduct = db.tblProducts.ToList()
.Where(x => Regex.Match(x.PrdKeyword, $#"\b{SearchText}\b", RegexOptions.IgnoreCase).Success)
.AsEnumerable();
Option 2. Without regexp:
public static bool CheckWord(string source, string searchWord)
{
if (source == null)
return false;
var punctuation = source.Where(Char.IsPunctuation).Distinct().ToArray();
var words = source.Split().Select(x => x.Trim(punctuation));
return words.Contains(searchWord, StringComparer.OrdinalIgnoreCase);
}
[HttpGet]
[Route("api/tblProducts/AllProductbySearch/{SearchText}")]
[ResponseType(typeof(IEnumerable<tblProduct>))]
public IHttpActionResult AllProductbySearch(string SearchText)
{
IEnumerable<tblProduct> tblProduct = db.tblProducts.ToList()
.Where(x => CheckWord(x.PrdKeyword, SearchText)).AsEnumerable();
if (tblProduct == null)
{
return NotFound();
}
return Ok(tblProduct);
}
Sorry, I'm from phone now, there can be mistakes here. Will try it in 3-4 hour
You are making a simple mistake. You just need to use .Equals instead of .Contains.
When you use Contains .Net will check if the input string is part of the main string. Whereas Equals will check for exact match.
var mainStr = “long string with Hello World”;
var inputStr = “Hello”;
var status = mainStr.Contains(inputStr);
// Value of status is `true`
status = mainStr.Equals(inputStr);
// Value of status is `false`
So your code should look like this:
IEnumerable<tblProduct> tblProduct = db.tblProducts.Where(x=>x.PrdKeyword.Equals(SearchText)).AsEnumerable();
.Equals can also help you find exact match with or without having case-sensitive check in force. The single-parameterised method does a Case-Sensitive check whereas the other overridden methods of .Equals gives you an opportunity to ignore it.
Hope this helps!
Our bot build does a ‘personality quiz’ for the user. Think Buzzfeed.
I have a variety of attributes I want to increase, just integers, based on the user’s selections on a form, then return an end result.
Using Sandwichbot as a template, this is asking something like (paraphrased):
Do you like to help other people? Yes No
Code is like:
.Confirm(async (state) =>
{
switch (state.HelpYesNo)
{
case true: HelpfulValue++; break;
case false: HurtfulValue++; break;
}
return new PromptAttribute("Thanks, choose OK to continue.");
It works fine, but I hate that I have to make the user ‘Confirm’ by typing OK. It’s an extra step, especially if they have to do it after each question.
I tried writing this with a validate instead, eg validate: async (state, response) =>
Which gives a better user experience, but doesn’t actually run the switch-case. I think the formatting of the switch is in the wrong place for a validate? I'm not sure of the syntax here to get 'validate' to process the case.
What’s the right way to do something like this in FormFlow?
Try something like this. Boolean fields also result in a Yes/No question.
[Serializable]
public class QuizForm
{
public int HelpfulValue;
public int HurtfulValue;
[Prompt("Do you like to help people? {||}")]
public bool HelpPeople;
public static IForm<QuizForm> BuildForm()
{
return new FormBuilder<QuizForm>()
.Message("Let the quiz begin...")
.Field(nameof(HelpPeople), validate: ValidateBool)
// other fields
.Build();
}
private static async Task<ValidateResult> ValidateBool(QuizForm state, object value)
{
var TrueOrFalse = (bool) value;
switch (TrueOrFalse)
{
case true: state.HelpfulValue++; break;
case false: state.HurtfulValue++; break;
}
return new ValidateResult{IsValid = true, Value = value};
}
}
I'm trying to set the date of birth of a person using jQuery Datepicker. However, all I get is that the Property dateOfBirth must be a valid Date.
So, originally, my controller looks like this:
def update(Person personInstance) {
if (personInstance == null) {
// do Something
return
}
if (personInstance.hasErrors()) {
respond personInstance.errors, view: 'edit'
return
}
// do the rest
}
I figured out, that with jQuery I should use a SimpleDateFormat object in order to generate a proper Date object. Nevertheless, even if I directly assign a new Date object to dateOfBirth and subsequently validating the personInstance domain object - like in the following code segment - I still get the Property dateOfBirth must be a valid Date error.
def update(Person personInstance) {
if (personInstance == null) {
// do Something
return
}
// added code
personInstance.dateOfBirth = new Date()
personInstance.validate()
// added code
if (personInstance.hasErrors()) {
respond personInstance.errors, view: 'edit'
return
}
// do the rest
}
Thank you for any help :)
The reason why you are still seeing errors is because validation is automatically called after binding your command/domain object when the method is called.
Use personInstance.clearErrors() before calling personInstance.validate() manually to clear out any existing binding/validation errors. You can see more about this in the documentation.
I'm trying to see if I need to write a custom IHttpRouteConstraint or if I can wrestle with the built-in ones to get what I want. I can't see to find any good documentation on this anywhere.
Basically, here's my action:
[Route("var/{varId:int:min(1)}/slot/{*slot:datetime}")]
public async Task<HttpResponseMessage> Put(int varId, DateTime slot)
{
...
}
What I want is to be able to call it like this:
PUT /api/data/var/1/slot/2012/01/01/131516 and have the framework bind 19 to var id and a DateTime with a value of "Jan 1st, 2012, 1:15:16pm" as the "slot" value.
Following the guide from here: http://www.asp.net/web-api/overview/web-api-routing-and-actions/create-a-rest-api-with-attribute-routing I am able to get it to work by passing in just the date segments, i.e. PUT /api/data/var/1/slot/2012/01/01 or PUT /api/data/var/1/slot/2012-01-01, but that only gives me a data value, no time components.
Something tells me that trying to pass in time in any sane way through URI segments is a bad idea, but I'm not sure why it'd be a bad idea, besides the ambiguity regarding local vs UTC times.
I've also tried constraining the datetime constraint with a regex, e.g. {slot:datetime:regex(\\d{4}/\\d{2}/\\d{2})/\\d{4})} to try to get it to parse something like 2013/01/01/151617 as a DateTime, but to no avail.
I'm pretty sure I can get this to work with a custom IHttpRouteConstraint, I just don't want to do something that might be built in.
Thanks!
an option is to pass the DateTime as query string parameters (see [FromUri]
e.g.
[Route("api/Customer/{customerId}/Calls/")]
public List<CallDto> GetCalls(int customerId, [FromUri]DateTime start, [FromUri]DateTime end)
this will have a signature of
GET api/Customer/{customerId}/Calls?start={start}&end={end}
Create the query string dates with
startDate.ToString("s", CultureInfo.InvariantCulture);
query string will look like
api/Customer/81/Calls?start=2014-07-25T00:00:00&end=2014-07-26T00:00:00
Web API datetime constraint doesn't do anything special regarding parsing datetime as you can notice below(source code here).
If your request url is like var/1/slot/2012-01-01 1:45:30 PM or var/1/slot/2012/01/01 1:45:30 PM, it seems to work fine...but I guess if you need full flexibility then creating a custom constraint is the best option...
public bool Match(HttpRequestMessage request, IHttpRoute route, string parameterName, IDictionary<string, object> values, HttpRouteDirection routeDirection)
{
if (parameterName == null)
{
throw Error.ArgumentNull("parameterName");
}
if (values == null)
{
throw Error.ArgumentNull("values");
}
object value;
if (values.TryGetValue(parameterName, out value) && value != null)
{
if (value is DateTime)
{
return true;
}
DateTime result;
string valueString = Convert.ToString(value, CultureInfo.InvariantCulture);
return DateTime.TryParse(valueString, CultureInfo.InvariantCulture, DateTimeStyles.None, out result);
}
return false;
}
I have a View Model called SignUp with the EmailAddress property set like this:
[Required]
[DuplicateEmailAddressAttribute(ErrorMessage = "This email address already exists")]
public string EmailAddress { get; set; }
and the custom validator looks like this:
public class DuplicateEmailAddressAttribute : ValidationAttribute
{
public override bool IsValid(object value)
{
PestControlContext _db = new PestControlContext();
int hash = value.ToString().GetHashCode();
if (value == null)
{
return true;
}
if (_db.Users.Where(x => x.EmailAddressHash == hash).Count() > 0)
return false;
else
return true;
}
}
The problem I'm having is that if the user leaves the email address field blank on the sign up form the application is throwing a null reference exception error (I think it's looking for "" in the database and can't find it). What I don't understand is why this isn't being handled by the Required attribute - why is it jumping straight into the custom validator?
The Required attribute would have resulted in an error being added to the model state. It will not short-circuit the execution though. The framework continues to run other validators for the simple reason that all the errors about the request need to be sent out in a single shot. Ideally, you wouldn't want the service to say something is wrong to start with and when the user re-submits the request after making a correction, the service comes back and say some other thing is wrong and so on. It will be an annoyance, I guess.
The NullReferenceException is thrown because value.ToString() is called before the check against null. As you need the hash variable only after the check, you can solve this by reordering the statements:
if (value == null)
{
return true;
}
int hash = value.ToString().GetHashCode();
In addition, you could also move the PestControlContext after the check against null and use a using statement to dispose of it properly.
As also #Baldri pointed out, each validator can add Error messages and all of them are run, even if a previous one already signaled the data to be invalid. Furthermore, I'd not rely on that the validations are run in the order that you specify when marking the property with the attributes (some frameworks implement their own attribute ordering mechanism in order to assert that the order is deterministic, e.g. priorities or preceding attributes).
Therefore, I suggest reordering the code in the custom validator is the best solution.